Pipe-wrench



(No Model.)

J. T. HAWKINS. PIPE WRENCH.

No. 404,619. v Patented June 4, 1889.

UJitF E55E5- lque fur- QM V FItturq 1 UNITE STATES PATENT OFFICE.

JOHN T, HAlVKINS, OF TAUN TON, MASSACHUSETTS.

PIPE-WRENCH.

SPECIFICATION forming part of Letters Patent No. 404,619, dated June 4, 1889.

Application filed December 7 I 1888. Serial No. 292,886. (No model.)

illustrated in the following specification and.

accompanying drawings.

The object of this, invention is to provide in the well -known solid alligator pipewrench an adjustable stop or tooth partially embedded in or lying upon the smooth jaw in such a way that the lateral strain brought upon said stop shall be transferred upon the jaw itself and said adjustable stop or tooth be supported by said jaw and applied to assist in the rotation of a pipe at the farthest point possible from the point of contact of the serrated jaw with the pipe.

The invention will first be described in detail, and then particularly set forth in the claim.

The instrument now well known as the solid alligator wrenchconsists of two jaws so constructed as to form a V-shaped opening between them, one of the jaws being toothed or serrated and theopposite one plain.. In the operation of such a wrench upon a pipe or rod the latter slides upon the smooth. jaw until the teeth or serrations on the opposite jaw take firm hold on the said pipe or rod. The tendency is found to be, however, in such construction, to more or less crush a pipe op erated on, under considerable rotative strain, by the forcing of the pipe still farther up into the V-shaped opening. It has been proposed to obviate this tendency by providing an adj ustable screw-stop passing through the vertex of the angle made by the inner surfaces of the two j aws. This latter construction is, however, open to the objection that the stop is apthest into the angle of the jaws. In this construction, also, the said stop cannot be madeto perform the function of a tooth or teeth without insuring transverse bending of the stop. Myinvention. however, provides an ad- 5 5 j ustable stop lying in a recess formed in the smooth jaw or lying upon and supported by the smooth jaw, so that said jaw may operate upon the pipe at the farthest point possible from the point of contact of the serrated jaw therewith merely as a stop, or be formed into a sharp tooth upon that side, and thus to provide against crushing by obstructing the further entrance of the pipe into the angle of the jaws after the serrated jaw has taken firm hold, and also to assist in rotating the pipeby acting as an abutment or stop or as a tooth, as may be preferred. v

In the accompanying drawings, Figure 1 illustrates in side view my invention applied to such a wrench; and Fig. 2 shows a trans verse view of the wrench, partly in section, on the center line of the adjustable stop-screw. Fig. 3 shows a side view of the jaw end of the wrench, with the point of the stop-screw pointed to serve merely as a stop without any action as an opposite tooth.

In said figures, thenumber 1 indicates the body of the wrench; 2, the serrated jaw; 3, the plain jaw, and 4 the stop-screw, threaded in its enlargement 5, formed upon the wrench for purposes of strength. In Fig. 1 the point of the stop-screw 4 is made square on the end, so as to form a sharp corner to penetrate the pipe and act as a nearly-opposite tooth. In Fig. 3 this point is tapered, so as to act merely as a sudden increase of angle of the jaws, to prevent further entrance of the pipe, which latter is shown as a dotted circle in Figs. 1 and 3. o

I do not claim, broadly, an adjustable stop; but

As of my invention I claim I11 combination with a pipe-wrench constructed of a serrated or toothed jaw, as 2, and an opposite smooth or unserrated jaw, as 3, forming an acute angle with each other, an adjustable stop or tooth, as 4, supported upon or within a recess formed in the smooth jaw and adjustable practically in line with said trance of and resulting tendency to crush said pipe, to assist as a nearly oppositely applied 10 stop or tooth in rotating said pipe, substantially as set forth.

JOHN T. HAWKINS. Witnesses:

ALBERT J. PARK, FREDERICK A. MERIGOLD. 

